Vehicle jack



G. A. COUNTRYMAN VEHICLE JACK Filed July 5, 1924 2 Sheets-Sheet 1 agpcialoz GUY A.Cour-rrzym Mar 23 1262.,

5. A. COUNTRYMAN VEHICLE JACK Filed July 5, 1924 2 Sheets-Sheet 2 I v I rum anoewfoz GuY A.COUHTEYMAH G mats hatented Mar. 23, 1925.

GUY ALVERTICE COUNTRYll IAN, OF ASHLAND, OHIO.

VEHICLE JACK.

Application filed July 3,

To aZZ co 20m it may concern Be it known that I, GUY ALv RTICE COUN- 'IRYMAN, a citizen of the United States, residing at 'rishland, in the county of Ashland and State of Ohio, have invented certain new and useful Improvements in a Ve' liicle. Jack, of which the following is a specification. I

My invention relates to an improvement in vehicle jacks of the double screw type, the iinproven'lent residing more particularly in the automatic stop mechanism hereinafter shown and described and claimed, whereby the :czews are prevented from unscrewing from each other and their common support while the jack is being operated. In general, my object is to provide a simple stop men her adapted to travel upwardly with one of the screws into direct stop engagement with a rotatable power-transmitting gear for the screws, and this stop member is also arranged and adapted to prevent the rotation of one of the screws while the other screw is being rotated by the gear.

In the accompanying drawing, Fig. 1 is vertical section centrally through a vehicle jack embodying my invention, the screws being shown nearly at their limit of upward travel with the stop member about to interrupt the rotation of the operating gear. Fig. 2 is a horizontal section of the jack on line 22 of Fig. 1 and Fig. 3 is a horizontal section on line 3-3 of Fig. 2. Fig. at is a perspective view of a modified form of stop member. Fig. 5 is a vertical section of the jack on line of Fig.1, showing the stop member raised to stop theoperating gear. Fig. 6 is a bottom view of the operating gear, and Fig. 7 a sectional I view thereof.

lhe jack comprises a tubular body or standard 2 having vertical channels 33 at opposite sides thereof. These channels e tend the full height of the standard and are open full length to the central chamber of the standard, and also open to the top of the standard where a rotatable bevel gear 4 is adapted to be seated. upon the standard within a recessed enlargei'nent 5. A bevel pinion 6 having an operating shaft 7 journalcd within an offset 8 of the standard may be used to rotate gear 4: which in turn is adapted to rotate ainain lift screw 9 having screwengagement with the internal screw-threads 10 at the upper end of the standard. Driving keys 11 fizied within gear 4- extend into 1924. Serial No. 724,007.

longitudinal side slots or key-ways 12 in screw 9, and the screw is flee to move vertically while gear 1- is held in a fixed rev oluble position upon the andard by a cover plate llhaving a central opening 15 for the screw. The bottom face of gear 1 is recessed and formed with one or more radial stop shoulders 16 which travel in a circle across the open top ends of vertical channels when gear l is rotated, thereby pern'iitting a stop member 17 to be projected into the recessed bottom of gear at wher stop shoulder 16 may engage the same during the rotary movement of the gear, providing the stop member has been raised to its limit in channel 3.

The means for supporting and ccntLolling the movement of stop member 17 consists of a rod or bar 18 which is -..,-pended from the bottom of a second tubular elevating screw 19 having screw-connection with the upper end of hollow lift screw 9. The

two screws and bar 18 are adapted to telescope together within hollow standard 2, and bar 18 is square in cross-section to prevent the inner elevating screw 19 from revolving while the main lift screw is being rotated by gear at, and bar 18 is prevented from turning b stoo member 17 which is in the form of a round rod with one end portion bent at right angles to provide a stop finger upwardly adapted to extend in channel 3, the opposite end of the rod being projected into the opposite channel 3. Stop member 17 also acts as a guide for bar 18, and if desired both ends of this member may be bent at right angles as shown at 20 20 in the modified form of stop member 21 in Fig. 4-. However, where only one end is bent at right angles the stop member may be readily removed from its receiving opening 22 at the lower end of bar 18 to permit said bar and screw 19 to be given a half revolution or more before replacing the stop member. whereby the two screws may be adjusted lengthwise in respect to each other in assen'iblying operations that one screw will not project beyond the other or engage the bottom prior to the other when the screws are fully telescoped within the hollow standard. A second opening may be used in bar 18 at right angles to opening 22 to permit quarterrturn adjustments, and such adjustments facilitate assemblying because in machining the threads it is ditheult to start the threads for each screw in Ill) the same place radially at the end of the SCI'QIV.

The bottom of hollow standard 2 is provided with a closure plate 2% and to prevent the screws from striking and dislodging this plate the standard is provided at its inner side with inwardlyextending ears or lugs 25 to arrest the descent of lift screw 9. Vhen both screws are fully telescoped within each other and the standard the tops of the screws are substantially flush with the top of cover plate 14:, and the angular stop member 1.7 is resting at the bottom of standard totation of gear & rotates the main lift screw 1) which is forced upward because of its screw connection with standard 2. Rotation of screw 9 imparts an inde 'iendent lift and extensible movement to the smaller elevating screw 19 which is free to travel vertically but is held from rotatioi'i by bar 18 and member 17. A ditierential movement takes place between the two screws, the upper or inner elevating screw 19 traveling faster than the lower or outer lift screw 9. As a result the inner elevating screw 9 will eventually pick up and lift bar 18 and carry the angular stop linger of member 17 into the bottom recess of revolving gear a where its upper end will be engaged by one of the stop shoulders 16 thereby preventing further revolution of the gear and further upward movement of the serene. This stopping action is timed to occur before the main screw can unscrew itself from standard 2. thereby preventing any possibility ot the jack from collapsing accidentally or by careless manipulation of the jack during lifting operations.

hat I claim, is:

1.. A vehicle jack, comprising a standard, a lift screw in screw connection with said s ai'ulnrd, a gear rotatably mounted upon said standard and splined to said screw, and telescopic means connected with said screw having a. stop member slidably engaged with. Lid s nulard adapted to engage said gear at its bottom during the final upward movement of said lijtt screw.

2. A vehicle aclr. comprising a standard, a main li'lt screw having screw connection with said standard, a second screw having screw connection with said main screw, an operating gear connected with said main screw and rotatably mounted upon said standard. a device adapted to slidably engagesaid standard to prevent rotation of sr id second screw. said device being adapted to travel upwardly with said second screw and carrying a stop member adapted to engage the bottom of said operating gear.

37-. A vehicle jack, comprising a channeled standard, a main lift screw having an operatinggear mounted upon said standard, a

second screw carried by said main screw having a device suspended therefrom adapted to travel in said channeled standard and prevent rotation of said second screw, and said device comprising an angular stop mean he]: a'liixed to its lower end adapted to engage and stop said operating gear.

at. A vehicle jack, comprising a tubular standard having a vertical side channel, a. main screw in screw-connection with said standard, a rotatable gear mounted upon id standard and connected with said main screw adapted to permit said screw to be elevated, a second screw in telescopic screw connection with said main screw, a bar suspended from said second screw having a cross piece adapted to travel in said side channel, said gear having a stop shoulder and -aid cross piece having an upwardlyer-itending part adapted to be elevated at one side oi" the lower portion of said main screw into stop relation with said shoulder.

5. A vehicle jack, comprising a main lift screw having an operating gear provided with a beveled stop shoulder at its bottom, and a. Iccond screw having a bar suspended therefrom provided with a vertically-extending stop member adapted to be raised into engaging position with said stop shoulder during the .[inal stages of upward movement of said lift screw.

6. A vehicle jack, comprising a main lilt screw having an operating gear, a second elevating screw operatively connected with said main screw, :1 bar suspended from said second screw, and a stop member detachably connected with said bar having a ver tical pro iecting linger adapted to be raised into stop engagement with the bottom of .aid operating gear.

7. A vehicle jack, comprising a hollow standard, a pair oi elevating screws and a bar adapted to be telescoped within said standard, vertical guides in said standard, a rotatable gear mounted upon said standard adapted to operate said screws having a stop shoulder at its bottom, and a cross member attired to said bar adapted to en- ;rr c said vertical guides, having a rightangled extremity extending upwardly atone side of said screws adapted to be enk by said step shoulder when said screws are elevated to approximately their maximum height.

3. A vehicle jack, comprising a hollow stannard, a pair of ele 'ating screws and an operating gear mounted upon said standard, said standard having a short inwardlyextending projection east integral at its bottom adapted to provide a stop rest for said screws when lowered into said standard.

In testimony whereof I my signature.

GUY ALVERTICE COUNTRYMAN. 

